The film has also been released on video as Bloody Mary (US) and Nights of Terror (UK).

[5] Carroll Baker plays a dual role in this film, two identical twins named Julie and Mary.

While in Holland, Julie begins receiving threats from some mysterious men who attempt to kidnap her, and one of them menaces her while wearing a gorilla mask.

They are confusing her with her twin sister Mary in London, who stole a massive diamond from a Maharaja and even betrayed her husband Craig, who was in on the heist.

A racecar driver named Tony (George Hilton) saves Julie from being kidnapped and hides her out in an apartment owned by an old blind woman, who later turns up murdered.